{
  "$comment": "MPLP Protocol v1.0.0 — Frozen Specification\nFreeze Date: 2025-12-03\nStatus: FROZEN (no breaking changes permitted)\nGovernance: MPLP Protocol Governance Committee (MPGC)\nCopyright: © 2026 Jearon Wong\nLicense: Apache-2.0\nAny normative change requires a new protocol version.",
  "$id": "https://schemas.mplp.dev/v1.0/common/events.schema.json",
  "$schema": "http://json-schema.org/draft-07/schema#",
  "title": "MPLP Base Event",
  "description": "Base model for all event structures in MPLP. Designed based on CloudEvents v1.0 core fields, providing unified event identification, type, source, and timestamp. ExecutionEvent, StateTransitionEvent, etc., are extensions of this.",
  "type": "object",
  "properties": {
    "event_id": {
      "$ref": "identifiers.schema.json",
      "description": "Unique identifier for the event (UUID v4)."
    },
    "event_type": {
      "type": "string",
      "description": "Event type identifier, e.g., execution.started / vsl.transition.applied / plan.created. Uses dot-separated namespace format.",
      "pattern": "^[a-z][a-z0-9]*(?:\\.[a-z][a-z0-9]*)*$",
      "examples": [
        "execution.started",
        "execution.completed",
        "vsl.transition.applied",
        "plan.created"
      ]
    },
    "source": {
      "type": "string",
      "description": "Event source, typically a module or component identifier. Can be a module name (e.g., 'context') or component path (e.g., 'runtime.ael').",
      "examples": [
        "context",
        "plan",
        "runtime.ael",
        "runtime.vsl"
      ]
    },
    "timestamp": {
      "type": "string",
      "format": "date-time",
      "description": "Event occurrence time (ISO 8601 format).",
      "examples": [
        "2025-01-28T15:30:00.000Z"
      ]
    },
    "trace_id": {
      "description": "Optional trace ID to associate the event with a specific Trace.",
      "$ref": "identifiers.schema.json"
    },
    "data": {
      "anyOf": [
        {
          "type": "object",
          "description": "Business data related to the event, constrained by upper-layer structures. Can be any JSON object or null."
        },
        {
          "type": "null",
          "description": "Business data related to the event, constrained by upper-layer structures. Can be any JSON object or null."
        }
      ]
    }
  },
  "required": [
    "event_id",
    "event_type",
    "source",
    "timestamp"
  ],
  "additionalProperties": false
}